Rotary radial piston machine



Sept. 6, 1966 K. EICKMANN 3,270,685

ROTARY RADIAL PISTON MACHINE Filed July 5. 1963 12 Sheets-Sheet 1 R 7 51 it 1 I INVENTOR.

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Sept. 6, 1966 K. EICKMANN 3,270,685

ROTARY RADIAL PISTON MACHINE Filed July 5, 1965 12 SheetsSheet eJNVENTOR.

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ROTARY RADIAL PISTON MACHINE Filed July 5. 1963 12 Sheets-Sheet 7INVENTOR. I64 R1. E/GKMANN BY hwewWL/iw Sept. 6, 1966 K. EICKMANN ROTARYRADIAL PISTON MACHINE E Q a .+b 5 C 0 y a I. m R, S m 2 r 1 n Y B QQQExb-u QQU A 101 Jf/S Sept. 6, 1966 K. EICKMANN ROTARY RADIAL PISTUNMACHINE 12 Sheets-Sheet 9 Filed July 3. 1963 INVENTOR. KARL E/C/(MA/WVBY 7K1) M M l2 Sheets-Sheet 10 Filed July 3. 1963 kWN MDN

JNVENTOR. KARI. E/C/(IVMN/V 12 Sheets-Sheet 11 Filed July 5. 1963 Wm mtkWh INVENTOR- KARL E/CKMANN Sept. 6, 1966 K. EICKMANN ROTARY RADIALPISTON MACHINE l2 Sheets-Sheet 12 Filed July 3. 1963 ll! 8 A/////// Q QINVENTOR.

KARL E/CKMAN/V BY 71H: ,m,

A rrozw s NW 9k United States Patent Ofi ice 3,270,685 Patented Sept. 6,1966 15 Claims. to. 103161) This invention relates to rotary radialpiston machines and, more particularly, to a rotary radial pistonmachine having plural groups of cylinders with each group includingplural cylinders, the axes of the cylinders of each group lying in acommon plane which is perpendicular to the axis of the rotor of themachine, and the respective groups of cylinders being spaced axiallyfrom each other. The machine is intended to operate with fluid such asliquid or gases in the cylinders, and may be used in the form of avariable or constant compressor, pump, hydraulic motor, rotarycombustion engine or the like in which the piston strokes, duringrotation, have either a constant or a variable length.

Such rotary radial piston machines are known, and include a plurality ofsubstantially radial cylinders formed in a rotor. Pistons arerecipro-cable in these cylinders during operation of the machine underpower, to increase and decrease the cylinder volumes inwardly of theinner ends of the pistons. Machines of this type have been very usefulin operation and in practical applications. However, it is stillpossible to increase the power output as well as the total efficiency ofsuch machines.

An object of the present invention is to provide a rotary radial pistonmachine having an increased power ouput and an increased overallefiiciency.

A further object of this invention is to provide a rotary radial pistonmachine including groups of cylinders each including plural cylindersarranged in a machine which has a relatively small overall size andweight in comparison to its possible power output.

In prior art variable output pumps or motors, it was not realized howimportant it is that such machines be of small size, small weight, andsimple in construction and operation while providing high power and highefficiency. Furthermore, insufiicient attention was paid to the factthat the liquid fiows must be accurately sealed from each other so thatthey cannot have adverse influences on each other resulting in failuresof the machines to perform properly. Furthermore, the relatively largedimensions of prior art machines results in relatively elongated pathsof movement between parts with corresponding increased friction, and thelow pressure of such machine results in the high percentage of losses inoutput power.

A further object of the invention is to provide a rotary fluid machineincluding plural cylinder groups each including plural cylinders, andwhich is compact and small in dimension compared with its power outputwhereby to lower its cost, to increase its etliciency and to increaseits useful life.

Yet another object of the invention is to provide a rotary fluid machineof the type just mentioned in which the increase in power output,efficiency and useful life is effected by shortening the paths ofrelative movement of adjacent parts, by balancing forces, by floatingmounting of parts, and by stabilization of the guiding of parts.

In accordance with the invention, there are at least two groups ofcylinders provided in the rotor. The axes of all of the cylinders of anyone group lie in a common diametric plane through the rotor. Thediametric planes of the several cylinders groups are spaced axially fromeach other. Consequently, by providing the plural cylinder groups, it ispossible to multiply the power output of the machine compared to one ofthe same dimensions but having only a single cylinder group. Thisresults in a decrease of friction relative to the power output andcoresponding increase in the efficiency.

Yet another object of the invention is to provide a rotary fluid machineof the type mentioned in which radial forces acting on the rotor arebalanced by dividing the cylinder-pistons into two groups with thepistons in one group always moving in the reverse direction with respectto the pistons in the other group, the two groups being equal in numberof cylinder-pistons.

A further object of the invention is to provide an arrangement wherebyeach cylinder group can have a separated flow, plural cylinder groupscan have separated flows, plural cylinder groups can cooperate for aprovision of the combined flow, each piston group can be driven by aseparated flow, plural piston groups can be driven by plural separateflows, and plural piston groups can be driven by a combined flow.

In accordance with a further object of the invention, a plurality ofcontrol ports are provided in a control body for cooperation with therotor and with passages leading to the cylinders in the rotor or rotors.

In accordance with another object of the invention, each guide means ofthe machine has at least three surfaces for guiding the pistons or thepiston guide shoe assembly during radial reciprocation, and in which thepistons or the piston guide shoes are guided radially inwardly by atleast one guide surface of the machine.

In accordance with the invention, it is possible to substantiallyeliminate friction on pistons and piston guide shoes and also to preventheating, sticking or welding of pistons, piston guide shoes and theiradjacent or guiding parts. It is further possible to obtain long pistonstrokes and thereby to increase the flow quantity through the machine,to balance radial forces acting on the rotor or rotors and on thepistons or the piston guide shoes, to provide a plurality of cylindergroups in the machine, to provide a plurality of separate fluid flowpassages in the machine, and to increase considerably the power andefficiency of this type of machine.

For an understanding of the principles of the invention, reference ismade to the following description of typical embodiments thereof asillustrated in the accompanying drawings.

In the drawings:

FIG. 1 is an elevation view of a piston guide shoe such as used in theembodiment of the invention shown in FIG. 16.

FIG. 2 is a sectional view taken along line IIII of FIG. 1;

FIG. 3 is a plan view of the guide shoe shown in FIG. 1;

FIG. 4 is an axial sectional view through one form of rotor embodyingthe invention;

FIG. 5 is a sectional view taken along the line VV of FIG. 4;

FIG. 6 is an axial sectional view through another form of rotorembodying the invention and taken along the line VI-VI of FIG. 7.

FIG. 7 is a diametric sectional view through the rotor of FIG. 6 andtaken along the line VII-VII of FIG. 6;

FIG. 8 is an axial sectional view through one form of guide ringembodying the invention;

FIG. 9 is an elevation view of the guide ring shown in FIG. 8 looking inthe direction of the arrow VIII-VIII;

FIG. 10 is an axial sectional view through another form of guide ringembodying the invention;

FIG. 11 is an elevation view of the guide ring shown in FIG. 10, lookingin the direction of the arrow XIXI;

FIG. 12 is an axial sectional view through a further form of guide ringembodying the invention;

FIG. 13 is a diamelrical sectional view through the guide ring shown inFIG. 12 taken along the line XIII XIII of FIG. 12:

FIG. I4 is a diametric sectional view through still another form ofguide ring embodying the invention and taken along the line XIVXIV ofFIG. 15;

FIG. 15 is an elevation view of the guide ring shown in FIG. I4 lookingin the direction of the arrow XV-XV;

FIG. 16 is an axial sectional view through a multi-cylinder group rotaryfluid machine embodying the invention;

FIG. 17 is an axial sectional view through another embodiment of rotaryfluid machine in accordance with the invention;

FIG. 18 is an axial sectional view through still another embodiment ofrotary fiuid machine in accordance with the invention;

FIG. 19 is a longitudinal sectional view through still anothermulti-fluid rotary machine embodying the invention; and

FIGS. 20, 2t and 22 are diagrammatic sectional views through FIG. 18taken along the lines XXXX, XXI XXI and XXIIXXII, respectively.

As stated, the present invention is directed to a rotary fluid machinein which there are a plurality of cylinder groups with each groupincluding a plurality of cylinders. Each cylinder has a pistonassociated therewith for reciprocation therein. In accordance with thepresent inven tion, the axes of the cylinders of each group lie in acommon diametric plane through the rotor or rotors of the machine, andthese planes are spaced axially from each other. In order to show thisimportant feature of the invention, the several planes are shown bysection lines such as the section lines 32 and 33 of FIG. 16, 132 and133 of FIG. 17, 232, 233 and 332, 333 of FIG. 18, and 432, 433 and 532,533 of FIG. 19.

The pistons 11 reciprocating in the respective cylinders are providedwith pivoted piston guide shoes. Referring to FIGS. 1, 2 and 3, apreferred embodiment of the piston guide shoes is shown as being similarto those of my allowed copending patent application Serial No. 229,644.As illustrated, each piston 1 has a trunnion portion 2 and a centralpart 4 which is integral with trunnion 2 and extends radially therefrom.The trunnion 2 is arranged to be oscillatably received in the usual slotprovided in a bore of the piston, such as the piston 11 of FIG. 7, sothat the guide shoes can oscillate about axes which are parallel to therotor axis.

Center part 4 of each guide shoe is provided, at each end, withcircumferentially extending or arcuate extension members 3 integraltherewith. These extensions have radially outer guide surfaces 5,radially inner guide surfaces 6, and radially extending end guidesurfaces 7. The several guide surfaces cooperate with respective guidesurfaces of stationary or rotary guide members. Referring to FIG. 4, thedual or twin rotor 8 is provided with two diametric planes, each havinga group of cylinders associated therewith, these planes being indicatedat 32 and 33. The axes of all the cylinders of one group are located inthe plane 32, and the axes of all the cylinders of the second group arelocated in the plane 33. Rotor 8 further has two annular ribs 34extending radially outwardly therefrom, each of these ribs beingcentered axially on a respective plane 32 or 33. Between ribs 34, therotor outer diameter is reduced by virtue of the annular recess 35 inthe outer surface of the rotor.

The piston guide shoes as illustrated in my mentioned allowed copendingpatent application Serial No. 229,644 are particularly suitable for usein the present invention since they are simple in design, stablytransmit traction and pushing forces in a substantial radial direction,and make possible long piston strokes. Consequently, this form of guideshoe is illustrated in the several embodiments of the invention.

Again referring to FIGS. 4 and 5, rotor 8 may have a rotor hub or axialbore 13, and it will be noted that FIG. is a sectional view taken alongthe diametric plane 33 of FIG. 4. A feature of the embodiment of therotor shown in FIGS. 4 and 5 is that the cylinders and 11 of therespective groups are aligned with each other in a direction axially ofthe rotor. Each cylinder communicates with the rotor bore 13 through aport and passage 14, and the bore forming each cylinder is drilledthrough the corresponding rotor rib 34 so as to provide slots 9 in theseribs.

FIGS. 6 and 7 show another embodiment of a twin rotor indicated at 15.This rotor is likewise provided with two groups of cylinders, one grouphaving the cylinder axes lying in the diametric plane 133 and the othergroup having the cylinder axes lying in the diametric plane 132. Thus,the axes of cylinder 16 lie in plane 133 and the axes of cylinder 17 liein plane 132 which is spaced axially from plane 133. As in theembodiment of FIGS. 4 and 5, each cylinder is provided with an axiallyextending slot 9 through the associated annular rib 52, there being twoof these annular ribs on rotor 15. As the bores forming the cylindersare formed through annular ribs, the slots 9 result providing the spacedwall portions having the arcuate inner surfaces 53 congruent with theinner surfaces of these cylinders.

The feature of the embodiment of rotor shown in FIGS. 6 and 7 is thatthe axes of cylinders 16 are angularly offset with respect to the axesof cylinders 17, with the axes of cylinders 16 lying angularlysubstantially midway between the axes of cylinders 17. Between theseveral cylinders, the exterior surface of rotor may be recessed asindicated at 18 to reduce the weight of the rotor or to provide spacefor parts cooperating with the rotor and the cylinders and pistons.Rotor 15 may be characterized as an angularly spaced twin rotor. FIG. 7also shows a piston 11 and its guide shoe 1 mounted in one cylinder.Furthermore, an annular recess 55 may be provided in the outer surfaceof rotor 15 between the two sets of cylinders, this annular recess lyingbetween the relatively narrow extensions 52.

Referring to FIGS. 8 and 9, a stroke ring 19 is shown which is mountedbetween two piston groups of the twin rotors. A feature of ring 19 isthat it can enter into the radially outer recess of the rotor 35 ofrotor 8 shown in FIGS. 4 and 5 or the radially outer recess 55 of therotor 15 shown in FIGS. 6 and 7. However, the stroke ring 19 of FIGS. 8and 9 is particularly suitable for cooperation with the twin rotor 8 ofFIGS. 4 and 5. Ring 19 has an annular radially outwardly extending ribor extension 22 whose outer surface forms a stroke ring seat 23 andwhose side surfaces form radially extending guide surfaces 21 and 24.Axially extending guide surfaces and 25 are provided on the outersurface of ring 19 on either side of the rib 22. The junction ofsurfaces 20 and 21 and the junction of surfaces 24 and 25, may berelieved as indicated.

Another form of stroke ring is illustrated at 27 in FIGS. 10 and 11.This is a twin stroke ring and therefore is provided with a pair ofradially outwardly extending and circumferentially interrupted flanges36 and 39, one at each end of ring 27. The radially outer surface ofring 27 between the flanges 36 and 39 provides a groove 31, which isgenerally channel-shaped. Stroke ring seats 27 and are provided by theradial outer surfaces of the flanges 36 and 39, and gaps or recesses 18are provided in the flange 36 and gaps or recesses 118 are provided inthe flange 39.

The twin stroke ring shown in FIGS. 10 and 11 is particularly suitablefor use in twin rotors wherein the diametric planes including thecylinder axes are relatively close to each other. The form of the ringshown in FIGS. 10 and 11 provides radially extending guide surfaces 28and 29 and an axially extending guide surface 20.

FIGS. I2 and 13 show another embodiment of the twin stroke ring providedwith a groove 31, ring seats 27 and 30, and flanges 36 and 39. Notches37 extend inwardly from one axial end edge of the ring, and notches 38extend inwardly from the other axial end edge, the notches 37 beingangularly staggered with respect to the notches 38. Radial guidesurfaces 28 and 29 are provided on the flanges, while the guide memberalso includes an axially extending guide surface 20. The twin ring ofFIGS. 12 and 13 is particularly suitable for use with the twin rotors ofthe type shown in FIGS. 6 and 7 and can enter into the radially outerrecess 55 or into the recesses 18.

The twin stroke ring shown in FIGS. 14 and has a design essentiallysimilar to that of the ring shown in FIGS. 12 and 13 but differstherefrom in that the flanges 39 and 41 have a much smaller axialspacing from each other than do the flanges 39 and 36 of FIG. 12. Thisembodiment of the twin ring is particularly suitable for twin rotorswherein the diametric planes including the axes of the cylinder groupsare closely adjacent each other axially of the rotor. The parts 40, 56,20, 44, 45, 48 and 49 of the ring shown in FIGS. 14 and 15 are similarto the corresponding parts 27, 30, 20, 28, 29, 38 and 37 of the ringshown in FIGS. 12 and 13. The junctions of the axially and radiallyextending guide surfaces may be relieved as indicated at 43.

FIG. 16 shows a rotary fiuid machine utilizing the rotor 8 of FIGS. 4and 5 and having the diametric planes 32 and 33 containing the axes oftheir respective cylinder groups. The stroke ring 22 shown in FIGS. 8and 9 is mounted between the two sets of piston guide shoes. Theradially extending guide surfaces 7 of. the piston guide shoes 1 haveguiding engagement with the radially extending guide surfaces 21 or 24of stroke ring 22, and also with the radially extending guide face 42 ofa support ring 54. A feature of this embodiment of the invention is thata rotatable ring 55 extends axially between the two support rings 54 andis carried by these two support rings thereby providing the axiallyextending radially inner guide face 56 which is in bearing engagementwith stroke ring 22 and which has guiding engagement with the radiallyouter guide surfaces 5 of the piston guide shoes of the two groups. Theradially inner guide surfaces 6 of the piston guide shoes having guidingengagement with axially extending guide surface 57 on support rings 54and with the axially extending guide surfaces and of stroke ring 22.Stroke ring 22 can enter recess between the ribs 34 of twin motor 8.

The machine shown in FIG. 16 has an outer casing 62 including a closure68 which fixedly supports a pintle 69. Rotor 8 is rotatable on a bushing58 on pintle 69, and is retained against axial displacement by retainingmeans 61. A shaft 63 may be connected to rotor 8 by clutch or couplingmeans 64 and is rotatable in a bearing 65. Support rings 54 rotate onbearings 66 which may be adjusted by an adjusting device 67 to controlthe relative eccentricity of the guide means with respect to the rotoraxis.

Pintle 69, or rather its support wall 68, is formed with connectionports 70 through which fluid flows to pintle passages 59 and 60. Ports14A and 14C connect passages 5-9 and 60, respectively, to cylinders 10through ports 14. Similarly, ports 14B and 14D connect passages 59 and60, respectively, to cylinders 10 through passages 14.

FIG. 17 shows another embodiment of rotary fluid machine in accordancewith the invention. In this embodiment, a stationary pintle 169 is alsoformed with passages 159 and 160 and with respective twin control ports114C, 114D, 114A and 114B. However, these ports are axially much closertogether than the corresponding ports in the embodiment of FIG. 16. Therotary support rings 54 of FIG. 17 are generally similar to supportrings 54 of FIG. 16, and the rotatable ring is generally similar to thering 5 5 of FIG. 16. A feature of the embodiment of the invention shownin FIG. 17 is that the twin rotor 15 of FIGS. 6 and 7 is used.Additionally, FIG. 17 illustrates how the twin stroke ring 39' of FIGS.14 and 15 is used. The two planes containing the axes of the respectivecylinder groups are shown at 132 and 133. The eccentricity adjustingdevice 67 acts in a manner disclosed in other variable rotor machinesshown in my patent applications and patents. The machine includes acasing 162 having an enclosure wall which is an integral extension ofthe pintle 169. The other parts are similar to those shown in FIG. 16.

The embodiment of the invention shown in FIG. 17 has two specialfeatures. The first feature is that, by virme of the angularly spacedtwin rotor" 15, the angular spacings between two circumfcrentiallyadjacent cylinders are relatively small and consequently the operationof the machine is relatively silent with only relatively smallvibrations and load changes. The second feature is that, using the rotor15, fluid machines may be built which are relatively short in an axialdirection.

FIG. 18 illustrates a multi-tlow rotary fluid operated or fluidoperating machine in accordance with another embodiment of thisinvention. In this embodiment of the invention, there are eight pintlepassages 112 through 119 formed in the control pintle 136 and eachassociated with a respective control port 120 through 127. The pintle136 also has connection ports 131, 130, 129, 128, 132, 133, 134 and 135each associated with a respective passage. Thus, pintle passage 112interconnects control port 120 and connection port 128, pintle passage113' interconnects control port 121 and connection port 129, pintlepassage 114 interconnects control port 122 and connection port 130,passage 115 interconnects control port 125 and connection port 131,passage 116 interconnects control port 127 and connection port 132,passage 117 interconnects control port 126 and connection port 154, andpassage 119 interconnects control port 124 and connection port 135.

All of the pintle passages extend through control pintle 136- and passfluid in either direction relative to the respective cylinders. Thepintle passages are sealed from each other and any communication betweenthe same is prevented. The connection ports are provided for connectionof pipes or tubes, and it will be noted that these ports are arranged inone group 128, 129, 130 and 131 and a second group 132, 133, 134 and135. During operation of the machine, one group of connection portsserves for flow of fluid into the machine while the other group ofconnection ports serves for exhaustiv fluid from the machine. It willtherefore be understood that the machine has four fluid inlets and fourfluid outlets. Machines of the type shown in FIG. 18 are therefore ableto drive machines, such as vehicles, which have at least four workingplaces or fluid motors, and prevents slip or free running between thedifferent motors.

The pistons in FIG. 18 have their axes in four different diametricplanes which are spaced axially from each other. The control ports and124 are associated with the group of cylinders having axes in the plane232. These two control ports are in diametric opposition, so that oneacts as a supply port and the other acts as an exhaust port.

Control ports 1'21 and are operatively associated with the cylindershaving axes in plane 233. These ports also are diametrically oppositeeach other, with one serving as an inlet port and the other serving asan exhaust port for the associated cylinders. Control ports 122 and 126,which are also in diametrically opposite relation, cooperate with thosecylinders which have their axes in the plane 333, with one control portacting as an inlet port and the other acting as an outlet port. Controlports 125 and 127 are operatively associated with those cylinders havingtheir axes lying in the plane 232. These ports, which are diametricallyopposite each other, act as inlet and outlet ports, respectively, forthe associated cylinders.

The machine shown in FIG. 18 includes cylinders 110 having their axes inplane 232, cylinders 112 having their axes in plane 233, cylinders 212having their axes in plane 333, and cylinders 210 having their axes inplane 332. In this embodiment of the invention, there are twoeccentricity adjustment devices 167 and 267 which may slide on guidesegments 567 as illustrated more fully in 7 FIG. 20. Part 267 is theinner adjustment device while part 167 is the outer adjustment device.An adjustment bolt 84 is provided and has oppositely directed threads 72and 73. Consequently, adjustment of bolt 84 results in movement ofadjustment devices 267 and 167 either toward each other or away fromeach other. If both adjustment devices are in the zero position, thestroke of the pistons is zero. However, if the adjustment devices arespaced widely from each other, delivery is a maximum because the pistonstrokes are a maximum. If the two adjustment devices are at theirminimum spacing, the flow of fluid through the machine is reversed andreaches a maximum because the piston stroke is also a maximum.

Those pistons having their axes in planes 232 and 332 move radially inunison with each other, while those pistons which have their axes inplanes 233 and 333 move in unison but in opposition to the pistons,having their axes in planes 232 and 332. Thus, if the pistons in planes232 and 332 are moving radially outwardly, then the pistons in planes233 and 332 are moving radially inwardly, and vice versa. Thus, thefluid forces acting on all of the cylinders against control pintle 136are entirely in balance it all the pistons have the same diameter and ifeach group of pistons includes the same number of cylinders.

The embodiment of the invention shown in FIG. 18 also provides the veryimportant feature of total balancing of the rotor and or the controlpintle, which provides for high pressure operation with high poweroutput and with a high efiiciency. Two twin rotors 8 may be used in themachine and may be rotatably mounted on a bush ing 158, the rotors beingfixed in position by a distance ring 258 and retaining means 61. Strokerings 119 may be provided, each cooperating with all of the piston guideshoes associated with pistons having axes in the same diametric plane.Guide member ring 71 may be provided to guide the stroke rings 119, therespective rotatable rings 154 and the respective support rings 254. Thesupport rings 154 and 254 are characterized in that they are supportedat one end only in bearings 66 and 166. The opposite ends bear againstthe respective guide rings 71. This arrangement saves space in an axialdirection. Support rings 154 and 254 may be integral with rotating rings155 and 255 and secured in position 'by rotating rings 161. The closure168 for the casing 162 may be integral with the pintle 163. A frontcover 74 and the back closure 168 are fastened in casing 172 byretaining rings or snap rings '75. The adjustment means, or moreparticularly the outer adjusting device 167, acts as a distance piecebetween front cover 74 and back cover 168 which eliminates the necessityfor further securing or fastening bolts and also saves space.

Other parts of the embodiment of the invention shown in FIG. 18 may actin a manner similar to other embodiments of the invention or as in theprior art, and it is therefore assumed that those skilled in the artwill understand their locations, functions and actions and that afurther detailed description is not necessary. The sections shown inFIGS. 20, 21 and 22 clearly illustrate the construction of theembodiment of the invention shown in FIG. 18. FIG. 21 illustratesanother embodiment of the rotor.

Referring to the embodiment of the invention shown in FIG. 19, this isanother entirely balanced rotary fluid machine. In this embodiment,there is only one inlet and one outlet flow and therefore only twoconnection ports 165 and 166 are necessary. A pintle passage 173interconnects control ports 169, 166, 167 and 172 with connection port165, and a pintle passage 174 interconnects control ports 165, 170, 168,and 171 with connection port 166. Control ports 165, 166, 167 and 168are visible in FIG. 19. Control ports 169 through 172 are not visiblebecause they are located in the diametrically opposite half of thepintle but in similar locations. Those pistons whose axes lie in theplanes 432 and 532 are moving radially inwardly at the same time thatthose pistons whose axes lie in the planes 433 and 533 are movingradially outwardly. The adjustment of the piston strokes and theadjustment of reversibility of flow is similar to that of the embodimentof FIG. 18.

A feature of the embodiment of FIG. 19 is the provision of a largernumber of hearings in order to provide stability for each rotating ringor each guide member. The piston guide shoes of pistons having theiraxes in planes 432 and 532 have guided cooperation with rotatable rings255 and support rings 254. The piston guiding shoes of those pistonshaving their axes lying in the planes 433 and 533 have guidedcooperation with the respective support ring 354, a rotatable ring 355and stroke ring 271. Since the pressure of fluid in those cylindershaving their axes in planes 432 or 532 acts in opposition to thepressure of fluid in those cylinders having their axes in planes 433 or533, the rotor or rotors float on control pintle 269.

Bearings 66 are mounted in the outer eccentricity adjusting device 467to rotatably mount rotary support rings 254 which carry the rotatablerings 255. Rings 255 and 254 may be fitted against each other, carriedby each other, or secured together by interfitting parts, such asgrooves and ribs, or by retaining means such as retaining rings. Supportrings 254 and rotatable rings 255 guide the reciprocation of the pistonsin cylinders having their axes in planes 432 and 532. The rings andtheir bearings 66 are located at adjacent opposite axial ends of theouter guide member or eccentricity adjusting device 467.

Inboard bearings 266 are located inwardly of the outboard bearings 66and mounted in the inner eccentricity adjusting device 367. Bearings 266support rings 354 which further support ring 355. Guide rings 371 arelocated between each inboard bearing 266 and the adjacent outboardbearing 66. Support rings 354 with rotatable rings 355 guide thereciprocations of those pistons operating in the cylinders having theiraxes located in the planes 433 and 533.

A twin rotor 15 is mounted on a bushing 458 substantially in the centerof the latter, and adjacent each end of twin rotor 15 there is a singlerotor 108 and 209 also mounted on the bushing 458. Control pintle 269either may be mounted in back cover 268, may be integral therewith, ormay be secured in casing 162. This pintle 269 may also be a floatingcontrol pintle such as shown in my British Patents 909,088 and 909,089.

The provision of the outer and inner adjustment devices 367 and 467 ofthe embodiment of FIG. 19 provides an especially stable structure as aresult of the planes of the cylinder axes being evenly spaced axially toeither side of the longitudinal center line of adjustment bolt 84. Dueto the balanced pressures, the rotors and the pintle float relative toeach other where-by the machine may have a high power and a highefliciency such as in the embodiment of FIG. 18 provided the pistons andcylinders are properly dimensioned and located.

The remaining components of the machine of FIG. 19 may be similar tothose in the other embodiments of the invention, may have functionssimilar thereto, or may be components known from the prior art, and itis assumed that those skilled in the art can understand the locations,principles and functions so that further detailed description does notappear necessary. Fluid pressure balancing recesses 78 can be providedin the outer surfaces of piston guide shoes 1, and may further beprovided on the control means or control panel or on the rotor orrotors.

It should be understood that insofar as there are disclosed controlpintles extending into respective rotor hubs, this by way of exampleonly. Instead of the illustrated control means, control means or controlbodies provided with plane, conical or spherical control faces, andwhich slide on the axial end faces of a rotor or rotors can be providedand suitably formed for control of the flow of fluid. The details of thedifferent embodiments of the invention may be used separately or incombination,

and detailed features of one embodiment may be also used in anotherembodiment. Furthermore, the fluid operated for operating rotarymachines can operate, or can be operated, either by liquid or gas. Itshould further be understood that the term fluid as used herein meanseither a liquid of a gas or something which has the ability to flow.

While specific embodiments of the invention have been shown as describedin detail to illustrate the application of the principles of theinvention, it will be understood that the invention may be embodiedotherwise without departing from such principles.

What I claim is:

1. A rotary fluid machine comprising, in combination, a casing; at leastone rotor rotatably mounted in said casing and formed with angularlyspaced radial bores constituting cylinders; pistons reciprocable in eachof said cylinders to vary the effective volumes of the cylinders todisplace fluid relative to said cylinders; guide means surrounding saidrotor and reciprocating said pistons upon rotation of said rotor; saidguide means having an eccentricity relative to the rotor axis to definethe piston strokes; said cylinders being arranged in at least two groupswith the cylinders of each group having their axes in a respectivecommon diametric plane through said rotor, said planes being spacedaxially of said rotor; said rotor having at least two external annularradial ribs each centered axially on a respective one of said diametricplanes, the axial widths of said ribs being less than the diameter ofthe associated bores; said guide means being formed to provide radiallyinwardly opening annular grooves arranged to have said ribs extend atleast partially thereinto; said bores being formed through said ribs toprovide extended guide surfaces for said pistons, with resultant axialslotting of said ribs at angularly spaced locations each centered on arespective cylinder axis; the cylindrical surface of said rotor beingformed, between axially adjacent ribs, to have said guide means move atleast partially close to it; whereby the effective piston stroke isincreased substantially relative to the rotor diameter; and fluid inletand outlet means communicating with said bores.

2. A rotary fluid machine comprising, in combination, a casing; at leastone rotor rotatably mounted in said casing and formed with angularlyspaced radial bores constituting cylinders; pistons reciprocable in eachof said cylinders to vary the effective volume of the cylinders todisplace fluid relative to said cylinders; guide means surrounding saidrotor and reciprocating said pistons upon rotation of said rotor; saidguide means having an eccentricity relative to the rotor axis to definethe piston strokes; said cylinders being arranged in four groups withthe cylinders of each group having their axes in a respective commondiametric plane through said rotor, said planes being spaced axially ofsaid rotor; said diametric planes being arranged in pairs spaced axiallyin balanced relation relative to a central diametric plane through saidrotor; the pistons in the two axially innermost groups moving radiallyoutwardly in their respective cylinders as the pistons in the twoaxially outermost groups move radially inwardly in their respectivecylinders.

3. A rotary fluid machine, as claimed in claim 2, including guide shoeseach operatively connected to a respective piston; said guide meanscomprising a first cylindrical guide means operatively engaged with theguide shoes connected to the pistons reciprocating in the axiallyinnermost pair of groups, and a second cylindrical guide meansoperatively engaged with the guide shoes connected to the pistons of theaxially outermost pair of groups.

4. A rotary fluid machine, as claimed in claim 2, in which said guidemeans comprises a first cylindrical guide means for reciprocating thepistons of the axially innermost pair of groups, and a secondcylindrical guide means for reciprocating the pistons of the axiallyoutermost pair of groups; and means for conjointly adjusting therespective eccentricities of said first and second cylindrical guidemeans in opposite directions.

5. A rotary fluid machine, as claimed in claim 2, said rotor beingrotatably supported on a pintle non-rotatably mounted in said casing;said pintle being formed with radial port means each communicating withthe bores located in a respective diametric plane, and being formed withplural connection ports in an axially outer end thereof and equal innumber to said radial port means; said pintle being further formed withplural axially extending passages each connecting a respectiveconnection port to a respective radial port means.

6. A rotary fluid machine, as claimed in claim 5, including a bushinginterposed between said pintle and said rotor and formed with radialports each registrable with the radial port means in a respectivediametric plane.

7. A rotary fluid machine, as claimed in claim 2, in which there arefour groups of cylinders, there being two groups on either side of thecentral diametric plane through said rotor, the four groups beingarranged in balanced relation with respect to said central diametricplane; each radial port means comprising a pair of diametricallyopposite radial ports, and there being eight of said connection portsarranged in two groups of four each; one group of four connection portsbeing connected to those radial ports on one side of an axial planethrough said pintle, and the other group of four connection ports beingconnected to those radial ports on the opposite side of said axial planethrough said pintle; one of said groups of connection ports being inletports and the other of said groups of connection ports being outletports.

8. A rotary fluid machine, as claimed in claim 7, in which the pistonsin the two axially inner groups of cylinders move simultaneouslyradially inwardly while the pistons in the two axially outer groups ofcylinders move simultaneously radially outwardly whereby the radialforces on said rotors and said pintle are balanced.

9. A rotary fluid machine, as claimed in claim 1, including guide shoeseach operatively connected to a re spective piston; each of said pistonguide shoes including a connection portion pivotally connected to theassociated piston for pivoting of the guide shoe about an axis parallelto the axis of said rotor, said connection portion having dimensionssuch as to fit within the associated cylinder, a mounting portionextending outwardly from said connection portion, a bar extending fromsaid mounting portion axially in both directions substantially parallelto the rotor axis and having a width such as to be able to enter withinthe axially extending slots of said ribs, and a pair ofcircumfercntially extending arcuate shoe portions each at a respectiveend of said bar.

10. A rotary fluid machine, as claimed in claim 9, in which said rotoris formed with recess means comprising a radially inwardly extendingrecess extending annularly of the cylindrical surface of said rotor;said guide means including a ring having a portion extendable at leastpartially into said annular recess; said ring having a pair of radiallyouter axially spaced guide surfaces engageable with radially innerarcuate surfaces of the guide shoes of pistons in axially adjacentgroups of cylinders; said ring including a substantially rectangular ribextending radially outwardly between said guide surfaces and havingradial guide surfaces engageable with the radially extending side edgesof the guide shoes of the pistons of axially adjacent groups ofcylinders.

11. A rotary fluid machine, as claimed in claim 8, in which said rotorhas an external annular radial rib centered axially of each diametricplane, the axial widths of said ribs being less than the diameter of theassociated bores; said guide means being formed to provide radiallyinwardly opening annular grooves arranged to have said ribs extend atleast partially thereinto; said bores being formed through said ribs toprovide extended guide surfaces for said pistons, with resultant axialslotting of said ribs at angularly spaced locations each centered on arespective cylinder axis; and in which there are four rotors including atwin rotor having a pair of said annular ribs and having the cylindersof the two axially inner groups arranged therein, and a pair of rotorseach axially adjacent a respective opposite end of said twin rotor andeach having formed therein the cylinders of a respective one of saidaxially outer groups of cylinders.

12. A rotary fluid machine, as claimed in claim 10, in which said guidemeans includes a second ring having a radially inner surface engagedwith the radially outer surface of the rib on said first mentioned ringand also with the radially outer surfaces of said arcuate shoe portions;said first and second rings being independently rotatable; and a pair ofsupport rings rotatably mounted in said casing in equal axial spacing tosaid first mentioned ring and peripherally supporting said secondmentioned ring; said support ring having circumferential guidingsurfaces engageable with the radially inner surfaces of the arcuate shoeportions of said guide shoes and radial guide surfaces engageahle withthe axially outer radial edges of said arcuate shoe portions.

13. A rotary fluid machine comprising, in combination, a casing; atleast one rotor rotatably mounted in said casing and formed withangularly spaced radial bores constituting cylinders; pistonsreciprocable in each of said cylinders to vary the effective volumes ofthe cylinders to displace fluid relative to said cylinders; guide shoeseach operatively connected to a respective piston; guide meanssurrounding said rotor and reciprocating said pistons upon rotation ofsaid rotor; said guide means having an eccentricity relative to therotor axis to define the piston strokes; said cylinders being arrangedin at least two groups with the cylinders of each group having theiraxes in a respective common diametric plane through said rotor, saidplanes being spaced axially of said rotor; each of said guide shoesincluding a connection portion pivotally connected to the associatedpiston for pivoting of the guide shoe about an axis parallel to the axisof said rotor, said connection portion having dimensions such as to fitwithin the associated cylinder, a mounting portion extending outwardlyfrom said connection portion, a bar extending from said mounting portionaxially in both directions substantially parallel to their rotor axis,and a pair of circumferentially extending arcuate shoe portions each ata respective end of said bar; the cylinders in axially adjacent groupsbeing staggered angularly with respect to each other so that, consideredangularly, the cylinders of one group are intermediate the cylinders ofthe axially adjacent group; said guide means including a guide ringdisposed between axially adjacent groups of cylinders and having aradially outer cylindrical guide surface engageable with the arcuateshoe portions on axially facing ends of the bars of the guide shoes ofthe two groups; said guide ring having flanges extending radially fromopposite edges of said cylindrical surface and engageahle with the sideedges of the arcuate shoe portions; said flanges being uniformlyangularly slotted, in staggered relation with respect to the twoflanges, to receive the bars of the guide shoes of the axially adjacentcylinder groups.

14. A rotary fluid machine, as claimed in claim 13, including a secondguide ring engaged with the outer cylindrical surfaces of said flangeson said first mentioned guide ring and engaging the radially outersurfaces of said arcuate guide shoe portions; and a pair of supportrings rotatably mounted in said casing and in uniformly axially spacedrelation to either side of said first mentioned guide ring andperipherally supporting said second mentioned guide ring; said supportrings having radially outwardly facing cylindrical guide surfacesengaging the radially inner surfaces of the arcuate guide shoe portionsof the adjacent cylinder groups and having radially extending guidesurfaces engaging the axially outer edges of the arcuate guide shoeportions of the guide shoes of the two axially adjacent cylinder groups.

15. A rotary fluid machine, as claimed in claim 11, in which said guidemeans includes a first cylindrical guide means and a second cylindricalguide means; said first cylindrical guide means including a first guidering engaged with the piston guide shoes of the two axially innercylinder groups; said second cylindrical guide means including a pair ofsecond guide rings each engaged with the piston guide shoes of arespective one of the two axially outer cylinder groups; means forconjointly adjusting said first and second cylindrical guide means as torelative eccentricity; a first bearing supporting said first guide ringrotatably upon a ring member engaged by said adjustment means; a pair ofsecond bearings each supporting a second guide ring, adjacent theaxially outer end thereof; on the second ring member engaged by saidconjoint adjustment means; and spacer means disposed between said firstring member and each of said second ring members.

References Cited by the Examiner UNITED STATES PATENTS 1,152,729 9/1915Hele-Shaw 103-161 2,454,418 11/1948 Zimmermann 103161 X 2,503,614 4/1950Eynard 103161 2,812,638 11/1957 Timms 103l61 X 2,895,426 7/1959Orshansky 103-161 3,120,816 2/1964 Firth et al lO-3-174 X FOREIGNPATENTS 801,060 12/1950 Germany. 881,058 11/1961 Great Britain.

MARK NEWMAN, Primary Examiner.

LAURENCE V. EFNER, Examiner.

J. C. MUNRO, Assistant Examiner.

1. A ROTARY FLUID MACHINE COMPRISING, IN COMBINATION, A CASING; AT LEASTONE ROTOR ROTATABLY MOUNTED IN SAID CASING AND FORMED WITH ANGULARLYSPACED RADIAL BORES CONSTITUTING CYLINDERS; PISTONS RECIPROCABLE IN EACHOF SAID CYLINDERS TO VARY THE EFFECTIVE VOLUMES OF THE CYLINDERS TODISPLACE FLUID RELATIVE TO SAID CYLINDERS; GUIDE MEANS SURROUNDING SAIDROTOR AND RECIPROCATING SAID PISTONS UPON ROTATION OF SAID ROTOR; SAIDGUIDE MEANS HAVING AN ECCENTRICITY RELATIVE TO THE ROTOR AXIS TO DEFINETHE PISTON STROKES; SAID CYLINDERS BEING ARRANGED IN AT LEAST TWO GROUPSWITH THE CYLINDERS OF EACH GROUP HAVING THEIR AXIS IN A RESPECTIVECOMMON DIAMETRIC PLANE THROUGH SAID ROTOR, SAID PLANES BEING SPACEDAXIALLY OF SAID ROTOR; SAID ROTOR HAVING AT LEAST TWO EXTERNAL ANNULARRADIAL RIBS EACH CENTERED AXIALLY ON A RESPECTIVE ONE OF SAID DIAMETRICPLANES, THE AXIAL WIDTHS OF SAID RIBS BEING LESS THAN THE DIAMETER OFTHE ASSOCIATED BORES; SAID GUIDE MEANS BEING FORMED TO PROVIDE RADIALLYINWARDLY OPENING ANNULAR GROOVES ARRANGED TO HAVE SAID RIBS EXTEND ATLEAST PARTIALLY THEREINTO; SAID BORES BEING FORMED THROUGH SAID RIBS TOPROVIDE EXTENDED GUIDE SURFACES FOR SAID PISTONS, WITH RESULTANT AXIALSLOTTING OF SAID RIBS AT ANGULARLY SPACED LOCATIONS EACH CENTERED ON ARESPECTIVE CYLINDER AXIS; THE CYLINDRICAL SURFACE OF SAID ROTOR